1. Field of the Invention
The present invention generally relates to the forming of inductive elements for electronic circuits. The present invention more specifically applies to the forming of an inductance in several superposed conductive levels.
2. Discussion of the Related Art
In the field of integrated circuits, where to form passive components using similar technologies, the bulk of an inductive element is generally desired to be reduced by superposing different conductive windings formed in successive levels. Such a superposition enables, among others, taking advantage of the mutual inductance effect between windings to increase the value of the inductance for the same surface bulk.
A problem which is posed is to decrease the number of vias required to electrically connect the different windings of the different levels without for all this to require an additional level only to perform these connections.
Another difficulty is to preserve the spiral superposition to keep the mutual inductance effect.